Automatic door-operating mechanism



May 1, 1928. 7 1,667,731

- B. s. HARRINGTON AUTOMATIC DOOR OPERATING MECHANISM Filed July e. 1926 2 sht -sheez 1 w II I i g v j 1" r-To I v I Q i= ?g -qjg j w May 1, 1928.

B. S. HARRINGTON AUTOMATIC DOOR OPERATING MECHANISM Filed July 6. 1926 2 Sheets-Sheet 2 fan, 3%

W v rlIlIlI/llllllllrlll%h y w mw fi 5 5 WW p k 5 Z.fl m r &u fig d Ill W655: w ww Patented May 1, 1928.

UNITED STATES IBERTIE s. HARRINGTON,

or FORT WORTH, Texas.

AUTOMATIC DOOR-OPERATING MECHANISM.

A pplication filed July 6,

The principal object of this invention is to provide an improved mechanism which, when -actuatecl, will automatically open a door, hold it open for a predetermined length of time, and close it at the expiration of such time.

Other obiectsand advantages of thein- .vcntion will be apparent to those skilled in the ant upon an understanding of the con struction, arrangement and operation of a mechanism embodying the invention. Such ,a mechanism presented herein for the purpose of eXenipli-fication, but it will' of course be understood t hatthe invention is also suscept'ible of embodiment various other modified forms comingequally within .the comprehensive scope of the appended claims.

In the preceding drawings:

1 is a perspective View of a door which is equipped with a mechanism' consti'uct'ed in accordance with the' invention';

Fig. 2 is a side elevation of the mechanism;

Fig. 3 is a vertical section through the mechanism; and I Fig. 4 is similarsection through a portion of the mechanism. v

It will be observed in the drawings that the door 10 to which the mechanism of the invention is ap plied is hinged in the usual way along one vertical edge, andhas attached to the opposite sides thereof two cords 11 and 12. The cord 11 is connected with a weight 13, and is trained over. two pulleys 1.4 and 15 in such a way ast-o tend'to' imll the door closed by thegravitationalforce exerted thereon by the weight 13. The cord 12 is connected with aheavi'er wei'glrit 16 which. is slidably mounted inan upright casin'gl'i, and is trained over a pulley 18 in such a way as to overbalance' the action of the weight 13 and pull the dooropen by the gravitational force exerted thereon bythe Weight 16. It will thus be seen that the two weights 13 and pull against the door in opposition to each other, the weight 16 being enough heavier than the weight ll'lto'ove'cron c the aifect ,of the latter and open the door and the weight 13 being siilficiently heavy to close tlixlddr when thexw'eight 16 is held against downward movement in the top of the tube-17. A hook 19 is pivotally mounted on the casing 17 i'ofittlie pur ose of holding the weight 16', and extends throughan aperture' in the easing into a position underlying the lower edge of the weight 16.

A person wishing the door to open simply 1926. Serial No. 129,604.

pulls upon either one of two cords {20 and 21, depending upon which side of the door The cords 20 and 21' he happens, to be on. are branches of a single operating cord22 which is trained over a pulley 23 and connects with alever arm :24 on the hook 19, and the resulting movement of the cord 22 swings the hook 19 outwardly and withdraws the same engagement with the bottom of the weight 16, whereupon the latter is permitted to move downwardly in the ca sing 17 and open thedoor gently under the modifying influence of the counterweight 13.

The weight 16 is provided witha longitudinally, extending bore 25, and slides up and down over a stationary piston 26 which is mountedon the upper end of hollow stem 27 connected with a source of air or other fluid under pressure As the weight 16 approaches the lower end of its travel, a 28 secured to the bottom of the 'hot :m of the jcasiijig 17, and the downward mminent of the weight is retarded and not cinnp'leted iiiit'il thcjoil 30 pocketed in the dash not has been expressed therefrom jthroug one or both of two small outlets 31 and 32 which are ustable as to size by means of suitable' -ne'edle valves 33. i

If .it isdesired-thet the door remain open comp rative y"Sh r p od, r s a c five seconds; the oil 30 in the'dash' pot 29 is permitted toileave the latter through both ava'lve E5" upwardly, thereby cutting oil communication between the dash pot-29 and the outlet 32, and causing all of the oil pocketed in tlie'dash pot to pass through the other outlet 31. c p

lVhen the weight 16 finally reaches the lower end of its travel, the valve 37' which shuts off theo'utlet 32 is shifted into-fininoperative position again. by the e-ngagr'eniei'it of-it shoulder 38 on the plunger 28 with the stem. of the valve ,bi'. At the same time, a

enters an oilffill'ed dash pot 29 in the smallfllever 39 'oiithc top of the piston 20 is depressed by engagement with the underside 40 of the top of the weight 16, and shifts Imitted to flow into the chamber l i, instantly raising the weight 16 to its uppermost position inthe casing 17 and thereby permitting the weight 13 to close the door. As soon as the weight 16 reaches the upper end of its travel, the hook l9 swings by gravity into its former position below and in supporting engagement with the bottom of the weight, and the upper surface 4L5 of the bottom of the weight engages with and lifts the stem of the valve 41 in the piston 26, shutting off communication between the compressed air passageway 42 and the port 43, and opening comn'uinication between the latter and a port 4:6 which communicates with a vented chain-- aer 46 in the weight below the piston 26. The operation of the machanism may be sunnnarized as follows:

in the normal closed position of the door, the weight 13 down, and the weight 16 up and latched in such position by the hook l9. l i hei'i a person wishc's'the door to open for a short period of time, such as for the purpose of permitting a single vehicle to pass therethro-ugh, he pulls the cord 20 (or 21) as he approaches the door with the truck. The movement of the cord 20 (or 21) is' transmitted to the cord 22, and the hook 19 is withdrawn from beneath the weight-'16, pern'iitting the weight to move downwardly and open the door. As the weight 16 approaches the lower end of its travel, it is retarded and does not bottom until tire seconds have elapsed, or any other period of time for which the valves 33 in the ports 31 and 32 have been set. As soon as the weight does bottom, however, the valve 41 in the stationary piston 26 is shifted downwardly by engagement of the under surface l of the weight 16 with the lever 39, and compressed air flows into the chamher 4% in the weight above the piston 26, thereby immediately elevating the weight 16 to its uppern'iost position, and permitting the weight 18 to close the door. When the weight reaches such position, the hook 19 reengages wlth and supports the same, and

the valve 41 is shifted downwardly by engagement of the stem thereof with the upper surface 45 the bottom of the weight, thereby establislnng communication between the upper closed chamber 44 in the weight and the lower Vented chamber 465. lVhen a person wishes the door to open for a compermit the passage therethrough of a train of trucks, he gives a longer pull on the cord (or 21), and the operation of the mechanism is substantially thesame as above described, the only difference being that the lug 34L on the rod 35 is shifted upwardly by the lever arm 24 and acts through the rod 35 and the lever 36 to raise the valve 37 and cut off the outlet 32 leading from the dash pot 29, thus forcing all of the oil 30 in the dash pot to flow out of the same through the other outlet 31 and requiring a proportionately longer period of time for such flow to be completed;

The mechanism of the invention is illustrated, described and claimed herein as used for opening and closing a door, but it will be appreciated that it might be used: with equally good results for'many other different purposes. The term door, therefore, as used in the claims, is intended to designate generally any kind of member capable of being moved in opposite directions.

I claim: n

1. A door-operating mechanism, including means for opening a door, means under manual control for actuating the opening means, and means operating automatically a predetermined length of time after the'door has opened for closing the same and plac- .ing the opening means in condition for operation again when actuated.

2. A door-operating mechanism, including means for opening a door, means for clos mg the door, and means operating automatically a predetermined length of tlme after the opening means has functioned forre-setting the opening means and causing the closing means to function.

3. A door-operating mechanism, including means for opening a door, means under manual. control for actuating the opening means, means for closing the door auto matically after the same has stood open a certain length of time, and means also'actuated by the means actuating the opening means for varying such time. 7

4. A door-operating mechanism, includ ing two weights, one of which is mounted in such a way as to tend to move a door in one direction, and the other of which is lighter and is mounted in such a way as to tend to move the door in the other direction, and means operable automatically a predetermined time after operation of the heavier weight for rendering the same inoperative whereby to permitoperation of the lighter weight.

5. A door-operating mechanism, including two weights, one of which is mounted in such a way as to tend to open a door, and the other of which is lighter and is mounted in such a way as to tend to close the door, and means for automatically raising the heavier weight a predetermined length of time after the lowering of the same and opening ofthe door whereby to permit lowering of the lighter weight and closing of the door.

6. A door-operating mechanism, including two weights, one of which is mounted in such a way as to tend to open a door, and the other of which is lighter and is mounted in such a way as to tend to close the door, a latch for supporting the heavier weight in its raised position, means releasing the latch to permit the heavier weight to open the door, a stationary piston disposed Within a chamber in the heavier Weight, and

means operating automatically after the, heav1er weight reaches its lowered position for conducting a fluid under pressure into the chamber above the piston, whereby to return the heavier weight to its raised and latched position and permit the lighter weight to close the door.

In testimony whereof I have hereunto subscribed by name.

BERTIE S. HARRINGTON. 

